Anyone who’s ever traveled knows that you’re never sure what the weather somewhere else will do to your hair. With the Kérastase Hair Coach Powered by Withings ($200), you can learn more about what’s happening to your hair and how to fix it. The brush can track a variety of factors like how you brush your hair and if you’re combing too vigorously, and it takes into account the humidity and wind levels in your area. With all this information, it gives you a score and recommends tips on what you can do to help your hair.